Height Definition and 1000 Threads

Homework Statement A ball is dropped from a sea cliff. 3.2 seconds later it is heard striking the water. The speed of sound is 340 m/s. How high is the cliff? I can't seem to get this question, every attempt seems to point to insufficient amount of information.

maximum height of a toy rocket?? Homework Statement A toy rocket is launched vertically from ground level(y=0) at time t=0s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 49 m and acquired a velocity of...

I'm having some difficulty with a homework problem which states: A cannonball is shot straight up out of a very powerful cannon located at the South Pole and reaches a maximum height of one Earth radius above the surface of the Earth. What was its initial speed? How long did it take to reach...

Homework Statement The question is as following: a) A dog in a stunt takes a jump off a rook which is 40 m high above the ground and lands on the next building which is of the same height , the gap between the two buildings is 6m @ the velocity of 8 m/s .Find the range of angles at which he...

Homework Statement A football is kicked straight into up into the air; it hits the ground 5.2s later. What was the greatest height reached by the ball? Assume its kicked from ground level. With what speed did it leave the kicker's foot? Homework Equations xf=xi + (vx)i +...

Homework Statement The speed of a projectile when it reaches its maximum height is 1/4 the speed when the projectile is at 1/4 its maximum height. What is the initial projection angle? Answer in units of ◦ Homework Equations v2 = v02 + 2a(delta s) 4Vx = v1/4 The Attempt at a Solution...

Homework Statement A flowerpot falls from the ledge of an apartment building. It takes .2 s for the pot to pass the 4 m window below. How far above the top of the window is the ledge from which the pot fell? (Neglect air resistance) Homework Equations y(t)=y0 + (voy)(t) - 1/2g(t^2)...

Homework Statement At which minimum height atoms or molecules are able to leave Earth’s atmosphere to space? To obtain an approximate estimate use the assumption that molecules can leave if the mean free path, λ, is larger than the scale height H. Write λ and H as a function of height and...

Homework Statement A coin tossed straight up into the air takes 2.75 s to go up and down from its initial release point 1.30 m above the ground. What is its maximum height? Homework Equations The Attempt at a Solution I seriously have no clue how to do this problem. I...

Homework Statement A student stands at the edge of a vertical cliff and throws a stone vertically upwards. The stone leaves the student's hand with a speed of v=8.0m/s, the acceleration of free fall is 10m/s2 and all distance measurements are taken from the point where the stone leaves the...

Homework Statement If it takes a fish 0.19s to perform evasive action, at what minimum height must it spot the pelican to escape? [Suppose a pelican starts its dive from a height of 15.9 m and cannot change its path once committed] If it takes a fish 0.19s to perform evasive action, at...

Spiderman steps from the top of a tall building. He falls freely from rest to the ground a distance of h he falls a distance of h/4 in the last 1.0 s of his fall. What is the height h of the building? The attempt at a solution is on the photo. I am stuck and don't know where to go...

Homework Statement Calculate the height of a cliff if it takes 2.35 s for a rock to hit the ground when it is thrown straight up from the cliff with an initial velocity of 8.00 m/s Homework Equations acceleration of gravity: 9.80 m/s2 ; not sure if I need to use -9.8 instead. the...

Homework Statement A projectile is launched with an velocity of 40 m/s and crosses a tower of height 20.4 m after 2 seconds. Find the angle of projection with the horizontal and the horizontal range. Homework Equations S = ut - 1/2 gt2 where S is the distance, u = 40 Sin\Theta and g...

Hi there, So I am doing this lab write-up at the moment with a single channel analyser. The following diagram pretty much sums up the setup: So pretty much I have found a suitable operating voltage gain by recording number of counts vs. gain and now I must change the Baseline-E...

Homework Statement Determine the minimum height of a wall mirror that will permit a 6ft person to view his or her entire height. Sketch rays from the top and bottom of the person, and determine the proper placement of the mirror such that the full image is seen, regardless of the persons...

Hello, I'm trying to simulate a projectile movement (without any air friction). But my projectile parameters are not conventional. I know : The initial height (y0) The initial velocity (v0) The maximum horizontal travel distance (d) The maximum height (h) I need to find ...

Homework Statement Been working on this for the past hour or so and seem to be going in circles; finally decided to call in the cavalry: You land on an unknown planet somewhere in the universe that clearly has weaker gravity than Earth. To measure g on this planet you do the following...

Homework Statement A handball is projected at an angle of 30 degrees with the horizontal from a 20 meter tower with an initial vertical velocity of 10 ms and an initial horizontal velocity of 20 ms. Find the total time of flight. Homework Equations The Attempt at a Solution I...

Homework Statement A baseball is thrown with an initial velocity of 20 ms at an angle of 30 degrees with the horizontal. How high did it go if it was released and caught 2 meters from the ground? Homework Equations The Attempt at a Solution 0=Vi^2 + 2ad 0=(20Sin30)2 + 2 X...

Homework Statement A child of mass 30 kg runs up a flight of stairs in 6 seconds. The top of the flight is 3 metres above the bottom, and at the top he is running at 2ms^-1. What average power does he need to produce? The Attempt at a Solution This is one of the first exercises I...

Homework Statement Nicole throws a ball straight up. Chad watches the ball from a window 6.10 m above the point where Nicole released it. The ball passes Chad on the way up, and it has a speed of 11.0 m/s as it passes him on the way back down. How fast did Nicole throw the ball? Homework...

Hi, I have the following problem that I would like to solve by using the 'fft' function in matlab. Some background on the problem: The evolution of sea surface height is given, to first order, by \eta_o(x,t)=A\cos\left(kx-\omega t\right) From this, we see that there are three parameters...

Homework Statement question is in the diagram. basically I am not sure how to use the specific gravity and convert it into pressure. Homework Equations P=p(rho)gh The Attempt at a Solution -

Homework Statement A 7500-kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.25 m/s^2 and feels no appreciable air resistance. When it has reached a height of 525 m, its engines suddenly fail so that the only force acting on it is now gravity. (a)...

Homework Statement The attachment shows the problem. The normal force at the top of the loop is 3 g's (as in g-force). Homework Equations PE = mgh KE = .5mv2 Fc = \frac{mv2}{r} PE + KE = PE' + KE' v = \sqrt{2gh} The Attempt at a Solution The normal force would be: 30 * mass...

Like people saying that drinking milk and sleeping right will make one grow taller, but is there seriously any effect at all? It's a genetics right? They say jumping or stretching make you taller, is that true?

Homework Statement An Earth satellite is to be put into orbit at a height of 2 Mm above the Earth's surface. Determine the velocity it must have. Make the following assumptions: (a) the orbit is circular; (b) the Earth is a sphere of radius 6•37 Mm; (c) gravity decreases as an inverse...

Homework Statement The triangular prism looks like this: http://www.korthalsaltes.com/photo/triangular_prism.jpg The triangles are "isosceles" triangles though, with the base facing down. However, this one is open on the bottom. They want me to find the height of the prism, when the area is as...

Ok, so I am trying to build myself a small water tank (about 1 L) with 2 tubes coming from the top. The first one goes all the way down to the bottom (thus in the water) and acts as the outtake. The second one is an air intake where the air pressure is regulated, say 5 psi. Now, I want to be...

This problem has 2 stars in my book, which means it is supposed to pretty difficult. I got the answer fairly easily and am worried that maybe I missed something important and thus got the incorrect answer too easily. No answer is provided to self-check my answer to see whether or not I am...

Homework Statement so if the original object is 4.6 cm tall located at x = 0 and it's a concave mirror distance from C to the object is 16 cm and Radius of the mirror is 12 cm The Attempt at a Solution to find the position of x image i got 9.6 cm then for magnification i...

Homework Statement A lens forms an image of an object. The object is 16 cm from the lens. The image is 12 cm from the lens on the same side as the object. (a) What is the focal length of the lens? Is the lens converging or diverging? (b) If the object is 8.5 mm tall, how tall is the image...

Well what do you guys and girls think. Does height play any role in attractiveness, offer any advantages in dating especially if you're a guy? It seems like for girls, they have to worry about how big their breasts, and "bums" are and for guys it's about how tall they are. Some girls...

the image of a tree just covers the length of a plane mirror 4.3 cm tall when the mirror is held 32 cm from the eye. The tree is 28 m from the mirror. What is the height of the tree? so I set up a ratio .043/.32=(28-.32)/h and solved for h and got 205 meters, but I am not sure if...

Firstly, I've been going over your forums for about fifteen minutes, and am taken aback by the intellect I have come across. I never took physics, but wish I had. Right out of high school, I went into construction, and never got the chance to go to college. I was always good at everyday Algebra...

Homework Statement A man drops a stone into a water well on his farm. He hears the sound of the splash 3.18 s later. How deep is the well? The acceleration due to gravity is 9.8 m/s^2 and the speed of sound in air is 316 m/s. Answer in units of m. Homework Equations x - x0 = v0t + (1/2)at2...

Hi, How do I find the height of the triangle , the triangle is set at 30 degrees and the length is 5 meters any help would be appreciated.

[b]1 A particle is projected with a velocity of 146m/s at an elevation of 35degree. max height= 357.8, t=17.1s horizontal distance= 2041.8m the question is find the velocity and direction of motion at a height of 120m i got v= 137.72, but what is the meaning of the direction of motion at...

Homework Statement I'm trying to calculate a value for gravity based on a known jump height and time. It's working when the take-off and landing heights are the same but I'm struggling for a solution if the landing point is higher than the take-off. I'm more interested in understanding a...

I'm taking an introductory geology class and am having big trouble with the math questions, as it's been many many years since I last took math classes. I am to use Archimedes Principle to calculate the thickness of continental crust beneath a certain coastal geographical point (at sea level...

Homework Statement I'm doing research with a professor at my college this summer on energy modeling for an electric vehicle. We're trying to figure out a way to make a model to predict how much energy an electric vehicle would need in order to do a certain path, but that requires testing of...

A roller coaster (475kg) passes point C with a velocity of 10.0 ms-1, calculate the velocity of the roller coaster at point A. mass = 475 kg velocity at C = 10 ms-1 height at A = 30m height at B = 0m height at C = 25m height at D = 12m Ep = mgh Ek = 1/2mv^2 The trolley is moving...

The scenario: I have a bag containing 3L of water, attached to a tube with the end placed on the floor (or a fixed height from the floor e.g. a bucket placed on top of a chair at 60 cm). I plan to hang this bag at heights of 100 cm, 120 cm, 140 cm, etc... until say about 200 cm from the floor...

Homework Statement When a 5kg mass is hung vertically on a light spring the spring stretches 3 cm. how much work must a external agent do to stretch the spring 4 cm from its equilibrium position? Because I am guessing it is hung vertically from the ceiling?

To calculate the height of a crane which is on top of a building, dennis measures the angle of elevation to the bottom and the top of the crane. these were 62 degrees and 68 degrees respectively. if the building is 42 metres high find the height of the crane. I'm asking for a friend, excuse...

To calculate the height of a crane which is on top of a building, dennis measures the angle of elevation to the bottom and the top of the crane. these were 62 degrees and 68 degrees respectively. if the building is 42 metres high find the height of the crane. I'm asking for a friend, excuse the...

Homework Statement "A boy throws a rock with an initial velocity of 3.13 m/s at 30.0 degrees above the horizontal. How long does it take for the rock to reach the maximum height of its trajectory?" vi = 3.13 m/s tmax height = ? vf = 0 m/s (at max height) a = -9.8 m/s2 Homework...

Homework Statement To find the height of an overhead power line, you throw a ball straight upward. The ball passes the line on the way up after 0.80 s, and passes it again on the way down 1.6 s after it was tossed. What is the height of the power line and the initial speed of the ball...

Homework Statement A 0.21 kg rock is projected from the edge of the top of a building with an initial velocity of 7.82 m/s at an angle 56 above the horizontal. Due to gravity, the rock strikes the ground at a horizontal distance of 10.5 m from the base of the building. How tall is the...